This invention relates generally to an arrangement for sensing position rate of change feedback information in a magnetic circuit such as may be used for rate damping and vibration suppression in a magnetic forcer system.
Sensing position rate of change (rate) feedback information for the purposes described has heretofore been accomplished using variations in inductance, eddy current properties and capacitance, or position differentiation. Rate feedback signals so provided are often noisy or, after differentiation, become sensitive to noise. The disadvantageous noise conditions are often the result of stray magnetic or electric fields, or stray capacitances when a capacitance sensor is used. The present invention, senses magnetic flux, or a parameter related thereto, and thus overcomes problems associated with the aforenoted noise conditions.